<p>查看python字节码的反汇编,您可能会得到一个更具体的想法</p>
<p>使用while循环:</p>
<pre><code>1 0 LOAD_CONST 0 (0)
3 STORE_NAME 0 (i)
2 6 SETUP_LOOP 28 (to 37)
>> 9 LOAD_NAME 0 (i) # <-
12 LOAD_CONST 1 (100000000) # <-
15 COMPARE_OP 0 (<) # <-
18 JUMP_IF_FALSE 14 (to 35) # <-
21 POP_TOP # <-
3 22 LOAD_NAME 0 (i) # <-
25 LOAD_CONST 2 (1) # <-
28 INPLACE_ADD # <-
29 STORE_NAME 0 (i) # <-
32 JUMP_ABSOLUTE 9 # <-
>> 35 POP_TOP
36 POP_BLOCK
</code></pre>
<p>循环体有10个操作</p>
<p>使用范围:</p>
<pre><code>1 0 SETUP_LOOP 23 (to 26)
3 LOAD_NAME 0 (range)
6 LOAD_CONST 0 (0)
9 LOAD_CONST 1 (100000000)
12 CALL_FUNCTION 2
15 GET_ITER
>> 16 FOR_ITER 6 (to 25) # <-
19 STORE_NAME 1 (n) # <-
2 22 JUMP_ABSOLUTE 16 # <-
>> 25 POP_BLOCK
>> 26 LOAD_CONST 2 (None)
29 RETURN_VALUE
</code></pre>
<p>循环体有3个操作</p>
<p>运行C代码的时间比intepretor短得多,可以忽略不计。</p>